Is there any even somewhat canonical word for 'medal' or 'medallion' in the Black Speech? If not, is 'gozg', a mash-up of the words for shield (goshur) and ring (nazg,) close enough for casual use?
I've seen references to a more expansive dictionary of Black Speech in this question: What do we know about the Black Speech of Mordor?, but haven't been able to find the notes that are referenced.
Why, you may be asking... well, I'm making a custom medal, and as a joke I want to put an altered version of the inscription on the One Ring onto it. The One Ring's inscription, in case you don't have it at hand, is:
Ash nazg durbatulûk, ash nazg gimbatul, Ash nazg thrakatulûk agh burzum-ishi krimpatul.
It's pretty, but it won't work as is, since I'm giving the person a medal, not a ring.